Copenhagen and Frankfurt would become the alliance's hub airports, Danish radio said, adding the cooperation would include coordination of routes, common ticket systems, administration and maintenance of the planes.

The German carrier, with its fleet of 250 planes serving 222 cities worldwide and staff of 50,000, is twice as big as SAS with 140 planes flying to 102 cities and employing 21,000 people, the radio said.

If carried out, the German- Scandinavian alliance would be among the largest carriers in Europe along with British Airways, the Berlingske Tidende said.